CEDAR RAPIDS, Iowa (AP) — Republican vice presidential candidate Paul Ryan defended himself Tuesday against lingering questions about the accuracy of some of his recent statements.

In interviews, Ryan disputed the notion that he misled voters in last week's convention speech while criticizing President Barack Obama's handling of debt reduction and the closure of a General Motors plant in his Wisconsin hometown. He also laughed off questions about why he understated his time in a marathon race by an hour.

Asked on NBC's "Today" whether he would agree that some of his statements have not always been accurate, he said, "No, not in the least, actually."

In an afternoon appearance in Cedar Rapids, Iowa, the 42-year old GOP congressman took the offensive against Obama, even as Democrats opened their convention in Charlotte, N.C., where they will nominate the president for a second term. Ryan aimed his remarks at the nation's weak economic performance under Obama.

"President Obama, to be charitable, he came into office with a very difficult situation," Ryan told the crowd. "Here's the problem: He made things worse. He's run out of ideas. And he cannot run on his record. That's why he's relegated his campaign to a campaign based on the politics of envy and division, smear and fear."

But in a round of morning broadcast interviews, much of the attention was focused on Ryan's own remarks at last week's Republican convention in Tampa, Fla. In his acceptance speech there, he linked Obama to the closure of a General Motors plant in his Wisconsin hometown, a plant that actually closed before Obama took office.

"What they are trying to suggest is that I said that Barack Obama was responsible for a plan shutdown in Janesville. That is not what I was saying. Read the speech," Ryan said on the "Today" show. "What I was saying is the president ought to be held to account for his broken promises. After our plant was shut down he said that he would lead an effort to retool plants like the Janesville plant to get people back to work. It's still idle."

Ryan was also asked about his acceptance speech criticism of Obama for rejecting the recommendations of a bipartisan debt-reduction commission the president appointed. Ryan did not mention in his convention remarks that he was on that commission and voted against the same plan.

"I didn't think it actually fixed the problem of runaway health care entitlement spending. I authored and passed through the House an alternative," Ryan, chairman of the House Budget Committee, told NBC. "The president didn't do that."

Both parties are often caught stretching the truth. But Ryan is facing near-daily accuracy questions just as many voters are still getting to know him, less than four weeks after Mitt Romney tapped him as his running mate.

Ryan, a former fitness instructor, recently told a radio host that he ran a marathon in less than three hours. Ryan released a statement correcting the record after Runner's World magazine found evidence he had completed one marathon, in 1990, and finished in just over four hours.

He was asked about his inaccurate recounting of his marathon time an interview that aired Tuesday on a Toledo, Ohio, television station.

"About my marathon you said?" Ryan laughed. "I literally thought that that was my time. It was 22 years ago. You forget sort of these things."

Ryan has been serving as the GOP ticket's leading aggressor in recent days. Romney is spending much of this week preparing privately for next month's presidential debates.

Campaign spokesman Michael Steel acknowledged that Ryan faced tough questions Tuesday morning, but suggested it was simply because it was some national news organizations' "first crack" at the Wisconsin congressman. Similar questions, however, have also followed Ryan this week in rounds of local interviews.

Meanwhile, Steel says that Ryan will not back down from any of his criticism of Obama's record.

"He's very prepared to answer questions about what he's said," Steel said.Associated PressCopyright 2012 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

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